/*
 * @Author: Clark
 * @Email: haixuanwoTxh@gmail.com
 * @Date: 2023-02-02 09:24:27
 * @LastEditors: Clark
 * @LastEditTime: 2023-02-02 12:48:11
 * @Description: file content
 */

#include "apue.h"

int main(void)
{
    int n, int1, int2;
    char line[MAXLINE] = {0};

    while ((n = read(STDIN_FILENO, line, MAXLINE)) > 0)
    {
        line[n] = 0; // null terminate
        if (2 == sscanf(line, "%d%d", &int1, &int2))
        {
            sprintf(line, "%d\n", int1 + int2);
            n = strlen(line);
            if (write(STDOUT_FILENO, line, n) != n)
            {
                err_sys("write error");
            }
        }
        else
        {
            if (write(STDOUT_FILENO, "invalid args\n", 13) != 13)
            {
                err_sys("write error");
            }
        }
    }

    exit(0);
}
